Tubular-arm sewing-machine



A. H. DE VUE.

TUBULAR ARM SEWING MACHINE.

APPLICATION FILED DEC- 4, 1917.

2 SHEETS-SHEET I.

Q INVENTOR MM fun/Q TTOHNEY M \Na Patented July 26, 1921.

A. H. DE VOE.

TUBULAR ARM swm0 MACHINE.

APPLICAHON FILED DEC. 4. \917.

1,385,364, Patented July 26, 1921.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

ALBERT H. DEVOEOF WES'I'FIELD, NEW JERSEY, ASSIGNOR TO THE SINGER MANU- I'AOE'UBING COMPANY, A conrone'rron or NEW JERSEY.

TUBULAR-Arm snwmo-mcnmn.

Specification of Letters Patent.

Patented July 26", 1921.

Application'flled December 4, 1017. Serial No. 205,316.

To all whom it may concern Be it known that LAmmwr H. DE Von, a citizen of the United States, residin at Westfield, in the county of'Union and tabs of New Jersey,rhave invented certain new and useful Improvements in Tubular-Arm Sewing-Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to chain-stitch sewing machines of thetype known as feed across-the-arm machines in which the work is supported on a hollow cylinder or tubulararin joined at one end to the frame of the machine and free at its other end. It is usually employed for stitching vamps in the manufacture ofshoes and it is es ecially useful for stitching circular or end esswork of varous kinds.

The object of this invention is to provide a new and improvedconstruction and a1- rangemcnt for operating the feed-dog and looper in a tubular-arm machine in order to obtain a strong, durable hi h speed machine. A further object of t is invention is to improvethe manner of securing the tubular-arm to the frame. And a still further object of thisinvention is'to compact and simplify the operating mechanism which must be housed within the narrow confines of the tubular-arm.

In its preferred form, the invention consists of aplurality of thread-carrying loopers operated from an inclined crank on the maiirshaft andlocated atthe forward end of the tubular arm, the loo ers being moved cndwise transverse and si ewisein the line of feed through a carrier" actuated from the inclined crank and fulcrumed on trunnionpins whose axis intersects the axis of the mainshaft. The feed-dog isjgiven four motions to advance the work across the arm through a pair of telescoping feed rock-shafts each actuated by an eccentric on the main-shaft and the length of stitch is varied through an adjustable connection accessible from the end of the tubular arm. p

In its preferred form the invention is illustrated in the accompanying drawings in which Fi ure 1 is a perspective view of the operating mechanism housed within the tubular arm which is indicated partly in dotted lines and partly in scctionfor the sake of clearness, the looper and looper-carrier being omitted also for the sake of clearness. Fig. 2 is a perspective view of the mainshaft and loopers operated thereby. Fig. 3 is alongitudinal section of'the free end of the arm taken on the line A-B Fig. l. Fig. 4 is an end view of thefree end of the tubular arm with the end cap omitted. Fig. 5 is an end view of the tubular arm, presserfoot and needles with the end cap in position. Fig. 6 is a perspective View looking at the inside of the end cap. Figs. 7 and 8 show in perspective the members of a linkage connecting the feed rock-shaft with the feed-dog carrier. Fig. 9'is a perspective of the feed rock-shaft and parts carried theroby. Fig. 10 is a perspective view of the feedlift rock-shaft. Fig. 11 shows the feed-dog carrier. Fig. 12 illustrates one of the sector plates carrying the bearings for the trunnion-pins of the looper-carrier. Fig. 13 shows a modified arm.

Rising from the feet or legs 1 is the vertical standard 2 having a boss 3 apcrturcd horizontally as indicated at 4 to receive the tubular or hollow arm 5 for supporting the work. .Any suitable means may be employed to secure the arm 5 within the boss 3, the set-screws 6 shown being simple and inexpensive means for that purpose. The boss is preferably made long c11ougl1.to get a good grip onthe portion of the arm inserted into it. The arm being lengthwise as Well as circumferentially adjustable in the boss may be readily located with the needle-holes in the throat-plate '7 in register with the needles 8.

The needles 8 in a clamp 9 on the needlebar 10 reciprocate through needle-holes in the usual pivoted presser-foot ll on the pressenbar 12 supported in the head of an overhanging arm (not shown) and operated in any suitable manner.

In its preferred form the machine is of the two-needle two'looper type for making a double thread chain-stitch but it is to be understood that the invention is not limited to the specific type of stitch-forming mechan1sm mentioned inasmuch as 1n certain respects the invention embraces other forms of mechanism. A singleneedle and looper for instance could be used as well as two or more of each and in some instances it might carrier 15 having trunnion-pins 16 extend-.

ing from opposite sides thereof into bearings 17 integral or in any other suitable manner fixed to the sector-shaped plates 18 see Fig. 12 which are removably secured by screws 19 to the arm on opposite sides thereof and whoseoutercurved surfaces define portions of the external surface of the arm. The trunnion-pins 16 are in a line and at substantially right angles to the blades of the loop ers 13. On the'trunnion-pins 16 and within thezbearings the loopers 13 may oscillate in planes parallel to the axis of the arm and may move bodily sidewise in a direction at rightangles to the planes of their endwise movements.

A socket 20 in the l0oper-carrier embraces a pin 21 carried by a sleeve 22 split in half and clamped together by the screws 23 so as to loosely and slidably embrace an inclined crank-pin 2 1 on the main-shaft 25 of the machine which is located in the lower portion and centrally of the arm directly beneath its longitudinal axis. The relation of the axes of the main-shaft of the inclined crank and of the trunnion-pins is important. The axis of the main-shaft 25 intersects the axis of the inclined crank 21 and slightly to one side of the'point of inter section the axis of the trunnion-pins 16 intersects the axis of the main-shaft 25. By reason of this relative arrangement the rocking of the pin 21 socketed in the carrier 15 not only imparts endwise movements to the loopers about the trunnion-pins as fulcrum, but also imparts bodily sidewise move ment thereto so that the loopers may enter the needle-loop on one side and retreat on the other side of the needle. From this description it will be seen that the looper is supported and actuated above and on the same side of the main-shaft of the machine. It will also be seen that the endwise and sidewise movements of the looper are positive and without lost-motion which is desirableand necessary to attain high speed in the operation of the machine.

Directly above the loopers 13 and the inclined crank 24 on the main-shaft is located the feed-dog 26, the serrated teeth of which are arranged to conform with the curvature of the arm. The shank 27 of the feed-dog is secured in a familiar manner between the ri s 28, Fig. 11, on U- ped feed-dog carrier 29. Projecting laterally from the opposite ends of the U-shaped feed-dog carrier 29 are pins 30 pivotally supported in bearings 31 at the free ends of crank-arms 32-33 one fixed and the other adjnstably clamped to a tubular shaft 31 which is rocked from an eccentric 35 on the mainshaft 25 through a pin-and-socket conueetion 36 best shown in Fig. 1. By these means vertical, components of motion are imparted to the feed-dog across the arm.

Horizontal components of motion are imparted to the feed-dog from an eccentric 37 (Fig. 2' only) on the main-shaft adjacent the lift eccentric and separated there from by a spacing collar 38. The st .'a p end 39 of a short pitman l0 embraces the feedeccentrie 37 and at its opposite end is pinned as at 41 to a crank-arm 4:2 fastened, in any suitable manner on a comparatively light feed rock-shaft 43 which extends through the tubular shaft 3 1 to the free end of the arm 5 where it is equipped with a second crank-arm 1 1 having a curved Tshaped slot 1 5 receiving a block 16 in which is tapped a screw 47 whose cylindrical head is nicely machined so that it may function as a crankpin. A washer 4-8 is interposed between the head of the screw 17 and the outer walls of the slot 15 so as to permit clamping ofthe block any desired distance in the curved T-slot 4-5 from the of the feed rock-shaft 43. Embracing the head of the screw 4.? is one end of a link 19. Fig. whose other end carries a pin 50 extending into an apertnred boss 51, Fig. 7, on a triangular shaped plate 52 having a bushing receiving the extreme end of the mainshaft 25 beyond the inclined crank 2i. the plate 52 being connected by a second link 5% to a curved and depending extension of the feed-dog carrier 29. Through the two links 4-9-54: and the triangular shaped plate 52, which is really a lever having a fixed fulcrum in the end cap 56 coaxial with the main-shaft. rocking movements of the feed rock-shaft impart horizontal components of motion to the feed-dog which com ponents may be varied in length.

The end-cap 56 of the machine is of the peculiar shape shown in perspective in Fig. 6 and in section Fig. It is cut away inside and at the lower rear portion to accommodate the slotted crank 44; and link 49 for imparting feeding movements to the dog, the link 1-9 which is removable being steadied against accidental displacement by the overlying wall 57 of the end-cap 56. This end-cap affords a bearing 58 for the bushing 53 and the main-shaft 25 which is indicated clearly in Fig. 3. The end-cap is accurately positioned upon the arm by the three clamp-screws 59 and by setting of a nose 60 againsta ledge 61 in a forwardly projecting and integral portion 62, F ig. 1,

lfl l ii i of the. arm. This bearing 58 for the mainshaft in the end-cap materially assists in confining the movements of the loopers to a fixed path and. preventing vibration and overthrow. thereof out of a fixed path.

. ascrew-driver for adjusting the position of the screw-pin 47 on the crank-arm 4A of the feed rock-shatt43 and thus regulating the feed to vary the length of stitch.

In addition to the bearing 58 in the end cap which receives the bushing ot the triangular plate 52 which in turn receives the extreme end of the main-shaft, the mainshaft is supported by a bearing 69 intermediate the length of the tubular-armand again by a bearing 70 adjacent the junction of the tubular-arm and: the vertical standard of the frame. These three bearings are the only bearings for the main-shaft ot the ma chine which shaft extends beyond the end of the tubular-arm into the vertical standard 2 where it is provided with a crank 71 embraced by the strap end of a pitman 72 suitably connected to the needle-bar operating sha'tt (not shown). The main-shattextends on through the end-wall. of the vertical standard 2 where it carries a beltnrheel 73 through which power is supplied for run ning the machine.

The telescoping rock-shafts 341 4 3 are journaled in a long bearing 74 exteiuling through and on opposite sides of the vertial plane ot the feed-motion and a relatively short bearing 7 5 immediately in rear oi the central bearing 69 for the main-shaft.

The feed rock'shaft 43 is provided with an additional bearing 7 6 beyond its crank-aria d2 which is operatedby the pitman embracing the teed-eccentric 37 on the main-shaft. it will be noticed that if across-section is taken through the junction of the tubular arm and frame that only a single shaft, the main shaft 25, will be out.

By telesroping the feed rock-shafts and by actuating them from the feed eccentrics on the main-shaft located intermediate the ends of the arm the mecl'ianism has been compacted within the cramped space avail.- able in the arm without sacrificing mechanical elliciency of operation. Furthermore, the short length of: the teles-ioping rock-shafts prevents any appreciable or prohibitive amount of torsion.

The thread is passed from the loopers 1.3

through the wire eyelet 77, Fig. 1, secured internally oi the arm and passing through an inclined hole 78 near the junction of the arm with the frame out to a take-up 79 constructedyand operated substantially in the manner fully described in. my copending appiication Serial No. 11 1-, )3, tiled August 12, 1916, but specifically"forming no part of the present invention.

Preferably the inclined crank 24 is formed on a small light shaft proportioned to carry the load imposed upon. it in actuating the loopers. This light shaft is socketed in a larger portion oi the main-shaft 25 as indieated at 80, F 2, and set screwed in place as shown at 81. Obviously, however, the main'shait may be made integral or otherwise it desired.

The manner of securing the tubular arm 5 to the vertical standard 2 of the frame is novel and advantageous. The arm alone carries the main-shat't and all the mechanism operated therefrom "for actuating the "feeddog and loopers. The mechanism is nicely. compacted within the arm. In the manufacture oi the machine the tubular arm may. thus be made complete in itself. In assembling the arm and frame together the former is inserted in the opening 4: of the boss 3 and the arm is readily positioned with the needle-holes in the throat-plate in line with the needle-paths by turning it about its own axis and by adjusting it lengthwise. litter positioning the tubular arm in this manner tightening of screw 6 will hold the tubular arm in proper position. No nice dimensioning oi parts within the tubular arm to link p with other members within the frame is o essary. The end oi? the pitman 72 being pl it may be readily strapped about the crank l. on the main shaft. By this simple manner of joining the arm to the frame the manufacture and assemblage of the parts within the tubular arm may be made expeditiously and accurately without the necessity of. precise measurement of any parts in the arm to link or connect up with a number of other parts in the frame. crank 71 and pitman 7 2 being the only driving connection between the mechanisms in, the ili l'ttllle and arm.

ln the feeding mecluinism the sustaining oi? the tend. dog carries on the opposite sides ot the plane in which the teed-- dog mores aliorcs a rigid support in suring against yielding of the teeddog under the strain of advancing the work and making its actioncertain and positive. The nesting oi? the teedrorlesha'tts economixes spare. Regulation oi: the teed being seldom necessary the simple adjustment ac ceasible through the end cap tor regulating the stitch length meets the demand and an swers the purpose without expensive additional parts in the form of levers, etc, heretofore employed.

In the loopermperating mechanism con1- pactness otthe organization without sacria bodily sidewise movement as well as an endwise movement, a single looper with an endwise movement only may be employed, if desired, by simply locating the bearings 17 for the trunnion-pins 16, so that the ax1s of the bearings will intersect the axis of the main-shaft at the same point as the axis of the inclined crank.

Attention is called to the fact that the adjustment of the block 46 in the curved T- shaped slot 45 to vary the length of feed effects variations at the rear end only of the feed-dogs stroke. In other words the feed- ClOg always rises and engages the work at the same point relative to the needles but it drops away and disengages itself from the work sooner or later depending on whether the stitch be short or long. This confining of the variation in the length of feed to the rear end of the feed-dog stroke is due to the fact that the center of curvature of the T- shaped slot 45 is coincident with the axis of pin 50 carried by the link 49 when the feed dog rises into engagement with the work. In other words the slotted crank-arm a4; arrives at neutral position relative to the link 49 when the feed is about to commence.

While the previously described form of tubular arm is preferred I contemplate the use of a modified form of arm shown in Fig. 13 which is similar in all respects to the preferred form'with the exception that an extension 5 thereof passes through the two opposed vertical walls of the standard instead of passing through the boss 3 only in one wall of said standard. An additional bearing 82 is carried by the extension 5 and the extension is cut away as indicated at and 84: to furnish clearance for the crank 7i and the pitman 72. In this modified form of arm the advantages of sustaining all bearings for the main-shaft on the tubular arm alone are preserved where the load on the main-shaft is too great to permit of locating the belt-wheel 7 3 as far away from the nearest hearing as is shown in Fig. 1. The advantages of having all the bearings for the main-shaft on the tubular armmay be partly realized by locating a bearing for the mainshaft in the end wall of the vertical standard adjacent the belt-wheel and it is to be distinctly undersood that such an arrangement is regarded within the scope of the invention in some of its aspects as defined by some of the claims.

It will be noticed by glancing at Figs. 2 and 5 that the supports (bearings 17) for the looper carrier are front and back of the line of needle actuation and that the supports (bearings 58 and 69) for the inclined actuating crank 24: are on opposite sides of the line of needle-actuation. It will thus be seen that there are two pairs of supports and if the members of each pair are connected by a straight line that the lines will cross each other at about right angles. Hence it will be seen that the looper carrier and its actuating inclined crank are each provided with hearings or supports on opposite sides of the line of needle-actuation.

Having thus set forth the nature of the invention, what I claim herein is 1. In a sewing machine, a frame having a tubular work-arm around which is a clear space facilitating manipulation of the work, a single rotating shaft only extending through the junction of the arm and frame, a feed-d0g, a looper, means for imparting four motions to said feed-dog and endwise movements to said looper from said rotating shaft, said means li einglocated entirely with in the tubular arm. 7 i

2. In a sewing machine, a frame having a tubular work-arm around which is a clear space facilitating manipulation of the work, a single rotating shaft only extending through the junction of the arm and fran'ie, a feed-dog, a looper, means for imparting four motions to said feed-dog and cndwise and sidewise movements to said looper from said rotating shaft, said means being located entirely within the tubular arm. I

3. In a sewing machine having stitchforming mechanism including a needle, a frame having a. tubular work arni, a single driving shaft only extending through the junction of the arm and frame, a fced-dog, a leoper, means for actuating said feed-din; to advance the work and said loopcr to cooperate with the needle in the formation of stitches. said means being located entirely vithi 1 the tubular arm and including a rockshaft disposed parallel to the driving shaft and of a length less than the length of said arm, said rock-shaft imparting to said feeddog movement in one direction, and means for imparting to said feed-dog movement in a direction at right angles to the first mentioned direction.

4. In a sewing machine having stitchforming mechanism including a needle, a frame havin a tubular work-arn'i. a single driving shaft only extending tl'irough the junction of the arm and frame, a feed-dog, a looper, means for actuating said feed-dog to advance the work and said looper to co operate with the needle in the formation of stitches, said means being located entirely within the tubula arm and including a pair of rock-shafts disposed parallel to the driving shaft and of a length less than the length, of said arm, said rock-shafts imparting to said feed-dog movements in a plane at right angles to each other.

5. In a sewing machine haying stitchforming mechanism including a needle, a frame having a tubular work-arm, a single driving shaft only extending through the junctionof the arm and frame, a feed-dog, a looper, means for actuating said feed dog to advance the work and for imparting endwise and sidewise movements to said looper, said means being located entirely within the tubular arm and including a rock-shaft disposed parallel to the driving shaft and of a length less than the length of said arm for imparting to said feed-dog movements in one direction, and meansfor imparting to said feed dog movement in a direction at right angles to said first mentioned direction.

(3. In a sewing machine having stitchforming mechanism including a needle, a frame having a tubular work-arm, a single driving Sllafi', only extending through the junction of the arm and frame, a feed-dog, a looper, means for actuating said feeddog to advance the work and for imparting endwise and sidewise movements to said looper, said means being located entirely within the trdmlar arm and. including a pair of rockshafts as disposed parallel to the driving shaft and of a length less than the length of said arm for imparting to said feed-dog movements in directions at right angles to each other. v y

'7. In a sewing machine, aframe having a tubular work-arm, a single rotating shaft onl extending through the junction of the arm and frame, a teed-dog arranged to opera to in a plane transverse the length of the tubular work-arm, a loop'er, means for actuating said feed dog to advance the work and for :inujiarting endwise movements to said looper, saidmeans being located entirely within the tubular arm.

3. Ina sewing machine, a frame having atubular work-awn, a single rotating shaft only extending through the junction of the arm and :lrame, a feed-dog arranged to operate in a plane transverse the length of the tubular work-arm, a looper, means for actuating said feed-dog to advance the work and for imparting endwise and sidewise increments to said loopcr, said means being located entirely within the tubular arm.

9. in a sewing machine having stitchforming mechanism, including a needle, a frame having a tubular work-arm, a rotating sha l't extending through the junction of the arn'i and frame, a feed-dog arranged to ()Ptll't'lifi in a plane transverse the length of said tubular arm, a looper, means for actuating said. feed-dog to advance the work and said looper to cooperate with theneedle in the torn'mtion of stitches, said means comprising a plurality of eccentric elements on said rotating shaft within the tubular arm and operating connections therefrom tothe fecd-d0g and loopcr.

y 1.0. in a sewing machine, having stichiha-ming mechanism including a needle, a frame having a tubular work-arm, a rotating shaft extending through the junction of the armand frame, a feed-dog arranged to operate in aplane transverse the length of said tubular arm, a looper, means for actuating said feed-dog to advance the work and said looper to cooperate with the needle in the formation of stitches, said means comprising a plurality of eccentric elements on said rotating shaft within the tubular arm and operating connections therefrom to the teed-dog and looper, said connections in cludii'ig a pin-and-socket device.

11. 111 a sewing machine having stitchforming mechanism including a needle, a frame having a vertical standard provided with a horizontally extending aperture, a tubular work-arm shaped in cross-section to fit said aperture within which. it is secured, a feed-dog and a looper operatively supported within said tubular arm adjacent its free end, means for imparting work-advancing movements to said feed-dog and stitch-forming movements to said looper.

12. I11 a sewing machine having stitchfori'ning mechanism includin; a needle, a frame having a vertical stanard provided with a horizontally arranged opening, a tubular work-arm shaped at one end to it within said opening, and having a throatplate provided with a needle-hole, clamping means for securing said arm within the opening in said vertical standard with the needlehole in line with the needle, work-feeding and needlecooperating devices movably supported within said tubular arm, and means for operating said devices.

1 ln a sewing machine having stitch- :im'ming mechanism including a needle, a frame having a vertical standard provided with. a boss having a horizontally arranged opening, a tubular work-arm shaped to fit within said boss and free to be adjusted lengthwise, clamping means for holding said arm in saidboss and permitting ad 1 ustment of the arm lengthwise in said openng as well as about its own longitudinal axis, a tl'eeddog, a looper, means for imparting movements to said feed-dog and looper to cooperate with the needle in the formation of stitches,

1.4:. In a sewing machine having stitchforming mechanism including a needle, a fraine'having a tubular work-arm, a mainshaft arranged within the work-arm, a feeddog operatively supported adjacent the free end of said tulailar arm, means for actuating said feed-dog in a plane transverse the tubular arm and from said main-shaft, said meansbeing located entirely Within the tubular work-arm, a looper, a looper-carrier mounted for oscillatory movement about a fixed axis directly beneath the feed-dog, and means for actuating said looper-carrier to cause the looper to enter and shed the loops thrown out by the needle.

15. In a sewing machine having stitchforming mechanism including a needle, a frame having a tubular work-arm, a mainshaft arranged within the work-arm, a feeddog operatively supported adjacent the free end of said tubular arm, means for actuating said feed-dog in a vertical plane transverse said tubular arm, and from said main-shaft, said means beinglocated entirely within the tubular work-arm, a main driving shaft, a looper, a. looper-carrier mounted for oscillatory movement about a fixed axis directly beneath the feed-dog, and connections between said main driving shaft and the looper-carrier for imparting endwise movements tothe looper.

16. In a sewing machine having stitchforming mechanism including a needle, a frame having a. tubular work-arm, a mainshaft arranged within the Work-arm, a feeddog operatively supported adjacent the free end of said tubular arm, means for actuating said feed-dog in a plane transverse said tubular arm, and from said main-shaft, said means being located entirely within the tubular work-arm, a looper, a looper-carrier mounted for oscillatory movement upon and for bodily movement along a fixed axis directly beneath the feed-dog, and means'for actuating said looper-carrier to cause the looper to enter and shed the loops thrown out by the needle.

17. In a sewing machine having stitchforming mechanism including a needle, a frame having a tubular work-arm, a feeddog operatively supported adjacent the free end of said tubular arm, means for actuating said feed-dog in a lanetransverse said tubulararm, a main driving shaft, a looper, a looper-carrier mounted for oscillatory movement about a fixed axis directly beneath the feed-dog, and connections between said main driving shaft and the looper-carrierfor imparting endwise movements to thelooper, said connections including an inclined crank on the main-shaft intermediate its ends,-and bearings for said main-shaft on opposite sides of theinclined shaft.

18. In a sewing machine having stitchforming mechanism including a needle, a

frame having a tubular work-arm, a feeddog operatively supported adjacent the free end of said tubular arm,-means for actuating said feed-dog in a vertical plane transverse the axis of said tubular arm, a main driving shafthaving an inclined crank intermedi ate its ends, bearings for said mainshaft on opposite sides of the inclined crank, a looper, a looper-carrier mounted for oscillatory movement about a fixed axis directly beneath the feed-dog, and means for actuating said looper-carrier to cause the looper .to enter and shed the loops thrown out by the needle. I

19. In a sew1ng mach1ne having stitchformingmechanism nclud ng a needle, a

frame having a tubular work-arm, a feeddog, a looper, and means for imparting oper' ative movements to said feed-dog and looper including a rotary main-shaft extending the entire len th of the arm and beyond the arm into the frame, and extensive bearing surface for said main-shaft carried solely by the tubular arm.

20. In a sewing machine having stitchforming mechanism including a needle, :1 frame having a tubular worlcarm, a feeddog, a looper, and means for imparting operative movements to said feed-dog and looper including a main-shaft extending the entire length of the arm and beyond the arm into the frame, a plurality of bearings for said main-shaft carried solely by the tubular arm, and means sustaining the tubular arm in the frame permitting lengthwise adjustment of the arm.

21. In a sewing machine having stitchforming mechanism including a needle, :1 frame having a tubular work-arm, a feeddog, a looper, a rotary main-shaft, means for imparting movements to said feed-dog and looper from the main-shaft, and bearings for said main-shaft supporting it on opposite sides of a vertical plane containing the line of scam formation.

22. In a sewing machine having stitchforming mechanism including a needle, :1 frame having a tubular work-arm, a feeddog and a looper operatively supported within said tubular arm adjacent its free end, a main driving shaft, a roek-shaft disposed parallel to said main driving shaft, connections between said feed-dog and rockshaft for imparting vertical components of motion to the feed-dog, bearings for supporting said rock-shaft on opposite sides of the vertical plane of feed, and means for imparting ho'q' zontal components of motion to the feed-dog.

23. In a sewing machine having stitchforming mechanism including a needle, a frame having a tubular wort arm, a feeddog and a looper operatively supported within said tubular arm adjacent its free end, a main driving shaft, a rock-shaft disposed parallel to said main driving shaft, connections between said feed-dog and rockshaft for imparting horizontal components of motion to the feed-dog, bearings for supporting said rock-shaft on opposite sides of the plane in which the feed-dog moves, and means for imparting vertical components of motion to the feed-dog.

24. In the tubular Work-arm of a sewing machine having stitch-for1ning mechanism including a needle, a looper, means for opcrating said looper, a main driving shaft extending within the tubular arm, said looper operating means being actuated solely from the main-shaft and being housed entirely within the tubular work-arm, a

men-$04 feed-dog, and means for imparting four motions to said feed-dog from said main driving shaft including a pair of parallel rock-shafts.

25. In the tubular worlearm of a sewing machine having stitch-forming mechanism including a needle, :1 looper, means for operating said looper, a main driving shaft, a feed-dog, and means for imparting four motions to said feed-dog from said main driving shaft including a pair of telescoping rock-shafts.

26. In the tubular work-arm of a sewing machine having stitclvforming mechanism including a needle, a looper, and means for operating said looper, a main driving shaft, a feed-dog, means for imparting four motions to said feed-dog from said main driving shaft including a pair of telescoping rock-shafts, and bearings for said telescoping rock-sl1afts on opposite sides of the vertical. plane of feed.

27. In the tubular work-arm of a sewing machine having stitch-forming mechanism including a needle, a feed-dog, a looper, a main driving shaft, means for actuating said feed-dogs from said main driving shaft including a pair of telescoping rock-shafts, bearings for said rock-shafts on opposite sides of the vertical plane of feed, and connections between said main driving shaft and said loopcr for imparting endwise and sidewise movements thereto, said main driving shaft having bearings on opposite sides of the vertical plane of feed.

28. In the tubular work-a rm of a sewing machine having stitch-forming mechanism including a needle, a main driving shaft located in the lower part of the arm, a looper, a loopei cai'rier mounted for oscillatory movement upon and for bodily movement along a fixed axis, an inclined crank ele-' ment on said main driving shaft, connections between the crank element and loopercarrier for imparting endwise and sidewise movements to the looper, and supports for both the loo ier-carrier and its actuating inclined crank on opposite sides of the line of needle actuation.

29. In the tubular work-arm of a sewing machine having stitch-f0rming mechanism including a needle, a looper, means'for operating the looper, a feed-dog mounted to function in a plane transverse the length of the arm, a feed-dog carrier, eccentric elements on the main-shaft within the arm, a pairof ro cleshafts actuated each by one of said eccentrics, arms on one of said roclb' shafts atopposite sides of the vertical plane of feed motion for-supporting and lifting said carrier to impart lifting movements to said feed-dog, anarm on the other of said rocleshaftsand connections from the lastnamed arm to the feed-dog carrier for imparting feeding movements to the dog, said connections being located between the vertical plane of feed motion and the tip end of the arm.

30. In the tubular work-arm of a sewing machine having stitch-forming mechanism including a needle, a main driving shaftlorated in the lower portion of said arm, a looper, means for actuating said looper from said main driving shaft, a feed-dog arranged to operate across the arm, a feed-dog carrier having a curved extension depending to a point adjacent the lower side of said arm, a pair of rock-shafts actuated independently from said mainshaft, armson one of said rock-shafts at opposite sides of the vertical plane of feed motion and pivotally supporting said carrier whereby the feed-dog is given its vertical components of motion, an arm on the other of said rock-shafts, and connections from the last-named arm to the feed-dog carrier for imparting horizontal components of motion to the dog, said 0011- nections including a lever having a fixed fulcrum below and immediately adjacent one of the pivotal supports for the carrier whereby the work-advancing movements to the feedalog conform to the external curvature of the arm.

31. In the tubular work-arm of a sewing machine having stitch-forming mechanism including a needle, a main driving shaft located in the lower portion of said arm, a loo per, means for actuating said looper from said main driving shaft, a feed-dog arranged to operate across the arm, a feed-dog car rier having a curved extension depending to a point adjacent the lower side of saidarm, a mir of rock-shafts actuated independently from said main-shaft, arms on one of said roclrshafts at opposite sides of the vertical plane of feed motion and pivotally support ing at their free ends said carrier whereby the feed-dog is given its vertical components of motion, an arm onthe other of said rockshafts, and connections from the last-named arm to the feed-dog carrier for imparting horizontal components of motion to the dog, said connections including a lever having a fixed fulcrum coaxial with the main-shaft below and immediately adjacent one of the pivotal supports for the carrier whereby the work-:ulvancing movements to the feed-dog conform to the external curvature of the arm.

In the tubular work-arin of a sewing machine having stitch-forming mechanism ineludin a needle, a main driving shaft 10- cated in the lower portion of said arm, a looper, means for actuating said looper from said main driving shaft, a fecd-dog arranged to operate across the arm, a feed-dog carrier having a curved extension depending to a point adjacent the lower side of said arm, a air of telescoping rock-shafts actuated in ependently from said main-shaft,

conform to the external curvature of the arm.

In the tubular work-arm of a sewing machine having stitch-forming mechanism including a needle, a main driving shaft lo cated in the lower portion of said arm, a looper, means for actuating said looper from said main driving shaft, a feed-dog a ranged to operate across the a m, a feeddog carrier having a curved extension depending to a point adjacent the lower side of said arm, a pair of telescoping rock-shafts actuated independently from said main-shaft, arms on one of said rock-shafts at opposite sides of the vertical plane of feed motion and pivotally supporting said carrier whereby the feed-dog is given its vertical components of motion, an arm on the other of said rockshafts, and connections fron the last-named arm to the feed-dog carrier for imparting horizontal components of motion to the dog. said connections including a lever having a fixed fulcrum coaxial with the main-shaft below and immediately adjacent one of the pivotal supports for the carrier v-rhert work-advancing movements to the feed-dog conform toithe external curva ure of the arm;

34. In the tubular work-arm of a sewing machine having stitch-forming mechanism including a needle, an end cap closing the freeend of said tubular arm, a main driving shaft, a looper, means for operating the looperfrom the main driving shaft, a feed dog, means for imparting work-advancing movements to'said feed-dog including an ad justable connection for varying the length I of feed accessible through said end cap Without removal of the same from the arm.

In a chain-stitch sewing machine hav ing stitch-forming mechanism including a needle, a frame having a tubular Workarm, and. housed within said arm looper, means for operating said looper, a main driving riations in the feed occurring at the rear end only of the feed stroke.

feed located between the free end of said tubular Work-arm and the vertical plane in which ti o food-dog moves.

3?. In a sewingmachine having a tubular work-arm, stitch-forming mechanism in cluding a needle, a rotar main-shaft within the tubular \vorlt-arm, an inclined crank on said rotary main-shaft intermediate its ends, a looper, a loopercarrier mounted. for oscillatory movement about a fixed axis. means for imparting oscillatory and bodily SitlQWlSQ movements to said loopcr-carrior including a sleeve provided with a cylindrical aperture adapted to embrace the in- (lined crank, and a pin-andsocket connection between the sleeve and the loopcr-carrier.

38. In a sewing machine having stitchforming mechanisms including a cooperating needle and loopcr, a frame having a vertical standard, a hollow \\'Oll(-lllill externally cylindrical at one end. said vcrt1- cal standard being providrd with a cylinl bore vvhose axis is substantially periculztr to that of the vertical standard, means for adjustably sccin'ing said can )1 cylindrical end of said work-arm in provided in the vertical standa rd. in a sewing machine having stitchf-nrning merhanism including a needle, a frame hating a. standard, a tubular workarm, a shaft Within said work-arm, workfeeding and looper mechanisms in said Work-arm, operative connections from hc shaft to the work-feeding mechanism andto the loeper mechanism for inniarting cndivisc and sidewise movements to the loopcr, aaui connections being supported Wholly by the work-arm and means for rcmovaliily securing the work-arm to the standard.

10. In a. sewing machine having stitchforming mechanism including a needle, :1 loop-taker, means for operating said looptal-ter, a main-shaft, a feed-dog, 11 ans for imparting four motions to said feed-dog inchidim a pair of telescoping shafts, driving conn trons from the main shaf "i one of said telescoping shafts for imparting hing and falling movements to the foul-dog and to the other shaft for imparting feeding movements to the feed-dog.

In testimony whereof I have signed my name to this specification.

ALBERT H. DE VOE, 

